The present invention is directed to an apparatus, system and method for retarding fire. The present invention is directed particularly to a fire-retardant barrier, a system which includes the fire-retardant barrier and a method which employs the fire-retardant barrier. The barrier retards fire from burning materials, such as buildings and other structures, forests and other vegetative materials, and the like. All of such materials, being combustible, are fuel for a fire if located in its path.
Wildfires are known periodically to threaten residential areas, and damage or destroy homes. Wildfires not only scorch acres of land by the hundreds of thousands, and destroy homes by the thousands, they are deadly. In early 2006, wildfires in the southern plains of the U.S. caused almost a dozen fatalities and necessitated the evacuation of 1,900 people as the flames raced across more the 1,000 square miles, while the resolute fight against the fires ‘from the ground and from the air’ consisted of dousing rooftops with water and dumping retardant from air-tankers.
In California, about 5.5 million acres are developed with housing unit densities meeting the Wildland-Urban Interface criteria and are at significant risk (very high or extreme risk) to damage from fire. “The Changing California, Forest and Range 2003 Assessment”, frap.cdf.ca.gov/assessment2003, October, 2003. California is not the only at-risk state. It has been reported that 80% of all housing units in New Mexico and Wyoming, and 40% to 55% of housing units in other Western states, including California, Washington and Oregon, are on land with fire potential. Typically, home owners have significant warning as to the likelihood of a fire passing through their residential area so that preventative steps can be taken to avoid damage, provided practical preventative measures are available.
Water has been known for millennia for its ability to prevent or extinguish fires due to its high heat capacity and high heat of vaporization. One method that has been used for retarding fire from burning a building is spraying water on the roof and exterior walls of a building. This method, however, is not particularly effective because water tends to flow off the building, limiting the amount of water that can be placed on, and adhered to, the building's exterior surfaces. Water also tends to evaporate quickly, especially in the heat of a fire. Covering a building with a tarp able to absorb water is also known, see U.S. Pat. No. 6,521,362.
It has been reported that foams or superabsorbent polymer gels formed by adding water to superabsorbent polymer powders have been used as a fire-retardant. However, forming and applying the foam or gel requires special equipment. Only limited amounts of gel or foam can be placed on a surface before the gel or foam begins to slough off. The gels and foams also can require significant cleanup after a fire has passed. Also, the concentrated polymers used to form gels typically are flammable, so that storage of the concentrated polymers can be hazardous.
Superabsorbent polymers have also been used in an insulating composite for body protection in extreme temperature situations. See U.S. Pat. No. 5,885,912 for a “Protective Multi-Layered Liquid Retaining Composite.”
What is needed is a method and a system that provide effective retardation of a fire, and an apparatus for retarding fire that is easy and safe to store, that is easy to apply to an object and/or area or locale, and that is easy to clean up after a fire has passed.